Ferns in the Present-Day Рeriglacial Zone of the Central Altai
I. I. GUREYEVA1, E. E. TIMOSHOK2
1Tomsk State University, 634050, Tomsk, Leninа аve., 36
2Institute of Monitoring of Climatic and Ecological Systems, SB RAS, 634055, Tomsk, Academicheskiy ave., 10/3
Keywords: папоротники, распространение, заселение, перигляциальная зона, Центральный Алтай, ferns, distribution, colonization, periglacial zone, the Central Altai
Abstract
Data on the species composition and distribution of ferns in the present-day periglacial zone of the Aktru, Karagemsky, Akkem, Sophiysky, Gebler and Taldurinsky glaciers in the Central Altai were presented. Sixteen species of ferns were found and confirmed by herbarium specimens. Botrychium lunаria (L.) Sw., Cystopteris dickieanа R. Sim, C. fragilis (L.) Bernh. and Polystichum lonchitis (L.) Roth were the most tolerant to the severe conditions of the high mountains. The distribution of ferns in the centers of present-day glaciation was related mostly to the occurrence of rocks. Colonization of the periglacial zone by ferns occured only by means of spores, initially by their dispersion from the locations far from the periglacial zone. Further colonization and migration of species following the retreating glaciers were possible by means of spores produced by sporophytes growing in the periglacial zone. Germination of spores and development of gametophytes and sporophytes in severe conditions of the periglacial zone occured mainly in local micro-niches providing protection in the cold season and sufficient amount of moisture in the warm season.
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